Margin status during the surgical treatment of solid tumors is the most critical factor in determining local recurrence rates. For breast cancer, breast conserving surgeries or lumpectomies are routinely performed. Currently, the surgeon is unable to visualize the microscopic structure at the margin, and conventionally relies on post-operative histological assessment of surgical margins to verify complete resection of the tumor. However, a critical intraoperative decision must be made to determine how much tissue around the primary tumor must be removed, or, where one must define the surgical margin. Therefore, a critical need exists to assess the surgical margin microscopically in real-time in the operating room, with spatial resolutions and pathological accuracies commensurate with post-operative histology, so that intraoperative feedback can be obtained during the surgical intervention. A partnership composed of collaborating academic, clinical, and industrial institutions and investigators will address this critical need by nonlinear interferometric vibrational imaging (NIVI). NIVI can images a wide variety of intrinsically vibrating biomolecules at a depth up to 1 mm with no labeling. The sensitive interferometric detection of quantitative Raman spectra allows NIVI to perform as a high-speed imaging analogue to Raman micro-spectroscopy. Through preliminary results obtained in our optical laboratory, we have demonstrated NIVI to have combined advantages of coherent anti-Stokes Raman scattering (CARS) spectroscopy and optical coherence tomography (OCT), and have successfully employed NIVI to detect tumor margins of breast cancer through specific abnormalities of endogenous biomarker molecules. This partnership will thus pursue the clinical translation of NIVI into an intraoperative imaging tool. The goal of this partnership will be achieved through a systematic approach. First, the extensive use of fiber-optic components will improve the robustness and the portability of the system, so that NIVI will largely retain the simplicity of a standard fiber-based OCT system. Also, an advanced handheld MEMS-scanner- based imaging probe will be incorporated into the system to flexibly access the surgical margin intraoperatively on resected tissue. Finally, the sensitivity and specificity of detecting positive margins will be determined to screen and flag margin locations suspicious for residual breast tumor. The successful completion of this project will result in a statistically-validated high-resolution molecular imaging technology capable of performing image-guided surgical interventions during breast cancer surgery. The intraoperative assessment of surgical tumor margin status has the potential to update and direct the surgical intervention in real-time, to reduce or eliminate reoperations, to minimize costs, and most importantly, to reduce the risk of local recurrence. Although the intraoperative imaging by NIVI in breast cancer surgery is the main focus of this project, we envision that this technique will benefit many other areas of surgical oncology. PUBLIC HEALTH RELEVANCE: Intraoperative imaging of the molecular abnormalities of tumor tissue with or without corresponding structural changes is useful to reduce re-operation rates, minimize costs, and provide point-of-care feedback for cancer surgery. Nonlinear interferometric vibrational imaging (NIVI) can image endogenous biomarker molecules without labeling, at spatial resolutions and pathological accuracies commensurate with post- operative histology, permitting real-time assessment of breast tumor margins during surgical interventions.